This invention relates to a formable reinforcing bar for structural support in construction applications and a method for making a formable reinforcing bar. More particularly, this invention relates to a formable reinforcing bar of a fiber reinforced thermoplastic material.
Reinforcing bars, or rebars, are employed for structural support in a wide number of construction applications. For instance, rebars are incorporated into concrete and various other materials in the construction of bridges, buildings, roadways and the like to provide additional support.
Traditionally, rebars have been manufactured from a metal such as steel or other metal alloy materials. However, traditional metal rebars have a number of significant disadvantages. Most concrete structures are exposed to moisture, acids and chlorine containing chemicals which slowly corrodes the metal over time. Thus, the lifetime of metal rebars is limited. Metal rebars are manufactured in a mill or other production facility in the desired end shape and then shipped, at high cost, to the construction site. By having prescribed lengths, metal bars must be cut to length at the construction site which causes waste and additional cost. They cannot be manufactured at a remote location, such as tee construction site. Further, metal rebars can only be shaped or formed at the construction site with significant effort to fit the varying needs arising during the course of construction.
In addition to metal reinforcing bars, rebars have also been made from reinforced thermosetting polymer materials. The thermoset polymers are reinforced with fibers to provide the required strength for structural support. These thermoset polymer rebars offer the advantage of being generally more resistant to corrosion than their metal counterparts. In addition, they generally weigh less than metal rebars, thereby reducing shipping costs.
Once a thermoset polymer is fixed in a particular shape, that fixed shape cannot be changed. In other words, a thermoset polymer may not be formed or manipulated once the polymer has cured. Accordingly, a thermoset rebar is not formable in the sense that the rebar can have its shaped changed on the job site to correspond with the changing construction environment. In addition, rebars of thermosetting polymers must be made in a manufacturing facility. Remote production is not possible as the thermoset rebar must be manufactured to its final dimensions immediately.
Accordingly, there remains a need for a corrosion resistant reinforcing bar for structural support in construction applications which is formable after the bar has been manufactured and which is capable of being manufactured in remote locations such as at a construction site.